1. Field of the Invention
This invention relates to a pipe coupling for joining axially aligned pipe sections.
Axially aligned pipes conventionally include a hub at one end for mating engagement with the opposite end of a similar piece of pipe. This conventional arrangement requires proper orientation of the pipe sections for sealing within the hub of the consecutive pipe section.
More recently, it has been found desirable to use hubless pipes because they are economical to manufacture and readily enable proper orientation with respect to each other. However, assembly of hubless pipes requires considerable precise axial force, without lateral force, to ensure proper sealing. Therefore, it is necessary to utilize a specialized tool for providing adequate mechanical advantage when assembling the pipe sections.
2. Description of the Prior Art
U.S. Pat. No. 3,682,503 to Bloom discloses a pipe joint for hubless pipe. The joint includes an outer sleeve and an inner gasket having a length extending beyond the overall length of the outer sleeve. Two hubless pipes are inserted into the central bore of the joint. The end faces of each pipe are urged inwardly toward a lip formed in the joint. The joint is assembled when the end faces of the pipe sections abut the lip. Although the pipe ends are inserted into the joint, Bloom provides no means by which to facilitate insertion.
U.S. Pat. No. 3,096,572 to Simmons discloses a pipe joint fabricating tool for assembling pipes having telescoping bell and spigot type joints. Each end of the assembly tool includes a jaw for maintaining engagement with the pipe during assembly. Teeth are provided at each end of the jaw for gripping the outer surface of the pipe. Where insertion of the pipe into the consecutive joint section requires substantial force, the jaw may scrape along the pipe, rather than allowing insertion of the end into the joint. This may result in wear of the teeth and erosion of the pipe with no mechanical advantage for assembly.